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Butynediol and its Derivatives

I'm looking for info. concerning butynediol or its derivatives when using it in a nickel sulfamate bath to control stress. I found several articles by Alec Watson citing its use as a leveler. Gabriel Schonwald also cited a technical note from Inco concerning its influence in a Ni-speed bath. I'm using it for optical mirror applications.

Chet Speegle
- Huntsville, AL
2000

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There are many articles on the chemical, as the results of a literature search should provide. It is a leveler and a brightener, and will increase tensile stress. I don't believe it would be used in electroforming, but it has been highly researched because it is very useful in bright nickel plating, so someone may have discovered other things about it.

  
Tom Pullizzi
Falls Township, Pennsylvania
2000

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I agree with Tom, I would not use butynediol as a stress controller, on the contrary.

Sara Michaeli
Tel-Aviv-Yafo, Israel
2000

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I agree that 1,4 butynediol is not a good stress reliever. According to Raub and Muller (in 1963) the optimum concentration of butynediol for stress relief is 8 mm/L (i.e., 0.69 g/l) . This could become difficult to analyse and control without good analytical techniques. Most diol containing solutions seem to operate at about 2 g/l.

Other levelers are known, such as coumarin and thiourea ⇦this on eBay or Amazon [affil links] ; the latter being the best. However, it is toxic and may have severe problems with discharge limits.

For a mirror bright deposit, I suggest you talk to your supplier as he will know the chemistry of the system better than anyone.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2000

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Hello all,

Procedure for the determination of butynediol. I am trying to determine the concentration of butynediol in an electroplating bath used for bright nickel plating. Any suggestions for doing this would be greatly appreciated!

Nathan Carrington
Process Electrochemist - Knoxville, Tennessee, USA
2007

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I'm not a chemist and don't know the methods, Nathan. Sorry. But it's used as an auxiliary brightener and I can tell you that ASM Metals Handbook Volume 5 says it's typically used between .01 and 0.5 oz./gal. Hopefully the typical concentration is a start on what procedures would b appropriate. Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2007